Keeping an eye on memory: how vision shapes episodic memory within naturalistic environments

'Episodic memory' is our memory for specific personal past events and experiences, such as our first day of school, or our first kiss. When recollecting these everyday memories, we often reconstruct the place and context in which the event took place in vivid detail. Indeed, the spatial layout of a scene appears to 'scaffold' and assist our ability to recall an episodic memory. For instance, without the ability to visually perceive the environment during memory encoding, the vividness of such memory appears to be significantly reduced during later retrieval. Further, recent neuroimaging studies suggests that brain regions thought to be responsible for episodic memory, such as the hippocampus, are also engaged when participants must perceive or tell apart visual scenes. This work suggests that understanding how we visually explore the spatial world may be critical for an in-depth understanding of how we encode and retrieve episodic memories. Despite this, the way in which visual scene processing shapes episodic memory remains largely unknown. For example, it remains unclear how visual scene perception influences the content and vividness of episodic memories, and which features are important for making a scene more memorable, and increasingly likely to be accurately remembered. This project aims to fill this knowledge gap by exploring the ways in which human visual scene processing shapes the recollective experience of episodic memory, as well as the underlying neural substrates.
To achieve this aim, this project will incorporate eye tracking, virtual reality (VR), novel scene memory tasks, and functional neuroimaging to examine how eye movements and visual attention within naturalistic scenes influences both behavioural and neural markers of episodic memory. Study 1 will use a novel scene drawing paradigm to measure the relationship between eye scanning patterns and the precision and accuracy of objects and features drawn during recall. Study 2 will extend upon this by utilising fully immersive 3D environments presented via a VR headset to assess the accuracy of memory recall when compared to the original scene which was explored during encoding, and how one's visual attention during physical exploration relates to the accuracy of recall. This experiment will account for the role of movement within a scene by using VR, thus representing what is typically experienced in real-world environments and situations. Finally, in Study 3, I will combine eye-tracking technology and functional neuroimaging to assess whether the degree of visual sampling of a scene is related to patterns of hippocampal activation at both encoding and retrieval.
Together, these studies will provide an understanding of how the visual system influences episodic memory by gaining insight into the activation of brain regions likely to be responsible for memory and visual scene processing. The proposed project will generate insights and alternative approaches to human episodic memory by exploring the potentially key role of scene vision. This will have important implications within the field of memory research, as well as having widespread benefits, such as potential support for visual processing and episodic memory processes that are subject to decline both in healthy, and pathological ageing. Additionally, this perspective will assist our understanding of the design of urban spaces, to make environments more navigable, and visually appealing. As well as having potential implications for video game industries, which aim to create an experience that is increasingly memorable for users. Therefore, this research could provide insight into ways to understand and support such processes to benefit individuals in society.